Organosilicon amine oxides and processes for their production



United States Patent M 1C6 q Patented Oct. 4, 1960.

groups and preferably the C,,H group is a polymethylene group and a preferably has a value from 3 to 5. 2955121 The siloxanes of this invention contain at least one ORGANOSILICON AMINE OXIDES PROC- I ESSES FOR THEIR PRODUCTION Roscoe A. Pike, Grand Island, EN.Y., assignor to Union Carbide Corporation, a corporation of New York No Drawing. Filed Dec. 29, 1958, Ser. No. 783,101

20 'Claims. (Cl. 260-4483) ticularly, this invention provides compounds represented V by the formula:

2 a 2a 3 1 P wherein R is a monovalent hydrocarbon group, a has a value of at least two, the R N(O) group is attached to at least the second carbon atom removed from the silicon atom and Z is a monovalent hydrocarbon group, an

alkoxy group, aryloxy group, a hydroxy group, a siloxy group or a R N(O)C,,H group. In Formula 1, R can be the same or difierent and Z can be the same or different. In Formula 1, the C,,H group is preferably a poly methylene chain, a preferably has a value from 3 to 5,

and preferably at least two groups represented by Z are alkoxy, aryloxy or siloxy groups. Illustrative of the monovalent hydrocarbon groups represented by R and Z in Formula 1 are the alkyl groups (e.g. the methyl, ethyl and propyl groups) and the aryl groups (e.g. the phenyl .40 Z in Formula 1 are the methoxy, ethoxy and propoxy,

group). Illustrative of the alkoxy groups represented by groups and illustrative of the aryloxy groups represented by Z is the phenoxy group. Preferably the monovalent hydrocarbon groups as represented by R and Z and the 1 alkoxy and/or aryloxy groups as represented by Z contain from 1 to 18 carbon atoms.

This invention also provides a process for producing compounds represented by Formula 1 which involves forming a mixture of an aminosilicon compound represented by the formula:

R NC H SiY wherein R and a have the above-defined meanings and Y I is a monovalent hydrocarbon, alkoxy, aryloxy, hydroxy, siloxy or R NC H group and an oxidizing agent and maintaining the mixture at a temperature at which the aminosilicon compound and the oxidizing agent react to produce, a compound represented by Formula 1. This process involves a reaction that can be illustrated by the The silanes of this invention can be represented by the formula:

2 a za 's wherein R and a have the above-defined meanings and Z is an alkoxy group, an aryloxy group, a monovalent hydrocarbon group or a R N(O)C,,H group. In Formula 3, R can be the same'or different and Z can be the same or difierent. Preferably at least two groups represented by Z' in Formula 3 are alkoxy or aryloxy group represented by the formula:

' v r/ R hl(0)Ca-HnS1O The siloxanes of this invention can contain, in addition by Formula 4, groups represented to groups represented by the formula:

1 R' SiO.

2 (5) wherein R' is a monovalent hydrocarbon group and c has a value from 0 to 3, preferably from 1 to 2. In Formula 5, R can be the same or different. Illustrative of the groups represented by R in Formula 5 are the alkyl groups (e.g. the methyl, ethyl and propyl groups), the

aryl groups (e.g. the phenyl groups), the alkenyl groups.

(e.g. the vinyl and the butenyl groups), the cycloalkenyl groups (e.g. the cyclohexenyl groups), the cycloalkyl' groups (e.g. the cyclohexyl group) and the aralkyl groups (e.g. the beta-phenylethyl group).

Suitable oxidizing agents include hydrogen peroxide, perbenzoic acid, peracetic acid and the like. The preferred oxidizing agent is hydrogen peroxide, especially when the aminosilicon compound contains Olefinically unsaturated groups.

oxidizing agents when the aminosilicon compound contains such groups. Olefinically unsaturated groups are unaffected by hydrogen peroxide.

' Suitable starting silanes can be represented by the formula:

R NC I-I SiY' wherein R and a have the above-defined meanings and Y is an :alkoxy, aryloxy, monovalent hydrocarbon or R NC,H group. Illustrative of the silanes rep-. resented by Formula 6 are N,N-diphenyl-gamma-amino propyltriethoxysilane, N,N dimethyl delta aminobutyl (methyDdiet-hoxysilane, N-methyl, N phenyl epsilonaminopentyl(dimethyl) ethoxysilane, N,N dimethylgamma-aminopropyl(trimethyl)silane, bis(N,N diethyl-- gamma-aminopropyl)diethoxysil-ane and the like.

Suitable starting siloxanes contain at least one group represented by the formula:

Y is a hydroxyl, alkoxy, aryloxy, monovalent hydrocarbon or R NC,,H group.

can be the same or different. Illustrative of the siloxane groups represented by Formula 7 are the N,N-diphenyl gamma-aminopropylsiloxy, N,N-dimethyl delta amino "butyl(methyl)siloxy, N-methyl, N-phenyl-epsilon-aminopenIY'KdimethyDsiloxy and bis(N,N diethyl gammaaminopr'opyDsiloxy groups and the like. Suitable start ing -siloxanescan contain, in addition to groups rep resentedbyFormula 7, groups represented by ForrhulaS;

' Suitable starting aminosilicon compounds can be pro' Perbenzoic acid and peracetic acid oxidize such unsaturated groups and so are less desirable:

, 2 1 p (7) wherein R, a and b have the above-defined meanings, and

In Formula 7, R and .Y" I

thread byforming a mixture of a chlorohydrocarbylsilicon I compound and a secondary amine and heating the mixture to a temperature sufiiciently elevated to cause the chlorohydrocarbylsilicon compound and the amine to react. This reaction'can be represented by the formula: R NH-{ -CI C HhSiEaR NC H S+Hl 8) wherein the R and a have the above-defined meanings;

Amounts of the oxidizing agent from 2 to 10 times the amount required tooxidizethe starting aminosilicon compound to produce the corres ondin amine oxide are useful but amounts from 5 to 6 times the amount required to oxidize the starting aminosilicon compound are preferred. No particularv advantage is; gained: by. using other amounts of thev reactants. Any excess oxidiZing agent canbedecomposed after the amine oxide. has. been formed by adding to the reaction mixture a reducing agent'such as. platinum or palladium either alone or supported on another material such'as gammaalumina or carbon. V

The starting aminosilicon compound and the oxidizirlg agent can be maintained at atemperature firom C. to 40 C., or preferably from 20 C. to 35 C. to cause them tovreact to produce an amine oxide. Although other temperatures can be used, no particular advantage is achieved by so doing.

The reaction of the starting aminosilicon compound and the oxidizing agent can be carried out within a solvent in which they are mutually soluble. Suitable solvents include water, chloroform, methylene chloride, acetone, alcohols, aqueous alcohols and the like. when hydrogen peroxide isthe oxidizing agent, the preferred solvent is water. When the solvent employed is water and the starting aminosilicon compound is a'silane rep-t.

resented by Formula 6 where at least one group represented by Z is an alkoxy or aryloxy group, oxidationof the amino group and, to some extent, hydrolysisv and condensation of the alkoxy or 'aryloxy occur to produce a siloxane represented by Formula 4. When perbe'nz'oic acid or peracetic acid is used as the oxidizing agent, anhydrous solvents (e,g. anhydrous chloroform) are used since these acids decompose in water. Amounts of the solvent from 10 parts to 150 parts by weight per 100 parts by weight of the startingarninosilicon compound and oxidizing agent are useful but amounts of the solvent from parts to parts by weight per 100 parts by weight of the reactants are preferred. It is usually not advantageous to use other amounts of the solvent;

The R N(O)C, H groups in the compounds of this invention readily decompose on heating to produce alkenyl groups. This decomposition reaction can be represented by the equation:

The decomposition reaction represented by Equation 9 amine oxides followed by conversionof the amine oxides to, alkenylsilicon compounds is a convenient way to make use of such tertiary which are often an undersired byproduct in the production of primary and/or secondary aminosilicon compounds. Furthermore, this route can be used toproduce alkenylsilicon compounds that are notreadily produced by other methods. 7

The alkenylsilicon produced 'bythe decomposition of the amine oxides of this invention are useful in a wide variety of applications. By way of illustration, the alkenylsiloxanes produced from the siloxanes of this invention can be cured via the alkenyl groups to produce resins or elastomers. As a further illustration, these alkenylsilicon compounds can be blended with other silicone materials and polymerized via the alkenyl groups to Pr v rp is ins n t e he mate a -H The yg t vn f en d y fl 3 and 4 is bonded only to the nitrogen atom. I do not wish to be bound by anyv particular theory regarding what type of chemical"- bond exists between thnitrogen ms n the que n. a ms is e, s pounds. q th invention; That is" it is possible" that these bonds are either of the type denotedby the symbol. N.- O (in which case my compounds would be represented by the formula:

o Ril lGsHi SiZs) or of the type denoted by the symbol N=O (in which case my compounds wouldbe represented by the formula:

I! mucnhsize is desirable to first: form a salt of these compounds and picnic acid and then analyze the salts so formed. These salts can be prepared. simply by mixing an alcoholic solution of the amine oxide and an aqueous solution of picric acid.

The following-examples illustrate the present invention.

Example I A mixture was formed containing 10 g. of N,-N-di methyl-gamma aminopropyltrimethylsilane and 20 cc. of methanol. The flask containing the mixture was cooled in ice and 20 g. of an aqueous hydrogen peroxide solution (containing 35 wt.-pe'rcent hydrogen peroxide) was slowly added to the flask over a 45 min. period. The solution was allowed to come to room temperature and to stand for 24 hours. The unreacted hydrogen peroxide was decomposed by adding to the flask 2 g. of platinum supported on gamma-alumina (2 wt.-percent platinum) and 2 g. of palladium supported on carbon black (0.5 wt.-perc'ent palladium). The mixture was stirred for 24 hours. The mixture was then filtered and the water was removed from the filtrate so produced by evaporating it at 1 mm. pressure at room tempera ture. There was so produced 9.5 g. of a semi crystalline, light green solid that had the formula:

Me mo crimsi'M'e The picrate salt of the latter compound was formed by dissolving 1 g. of the compound in methanol and OsN N0:

[Me N(0)(CHi)iSiMeil Not This compound melted at l4 7-l48 C. and had the following analysis:

The amine oxide (8.0 g.) produced in Example I was heated in a nitrogen atmosphere at mm. pressure in a flask attached to a Vigreaux column and two traps in series. The first trap was cooled in Dry Ice-acetone mixture and the second in liquid nitrogen. The flask was heated at a rate of 2 to 3 C. per minute. Decomposition of the amine oxide began at 90 C. and was completed at 100 C. No residue remained in the flask. Essentially all of the distillate was collected in the first trap. The distillate collected in the first trap was acidified with 0.1 N hydrochloric acid. The two layers formed: an aqueous layer and an organic layer. The aqueous layer was frozen by immersion in Dry Ice. The organic layer was separated with a pipette and distilled through a semi micro column. There was so produced 4.69 g. of allyltn'methylsilane which had a boiling point of 83-85" C. at 747 mm. and n =1.405l. The aqueous layer was melted and the water was volatilized at reduced pressure. Absolute ethanol was added and the ethanol and the residual water was volatilized at reduced pressure. The residue so produced was 2.5 g. of Me NOH.HCl.

What is claimed is:

1. An amine oxide selected from the group consisting (A) a silane represented .by the formula:

wherein R is a member selected from the group consisting of the aryl groups and the alkyl groups, a has a value of at least two, the R N(O) group is attached to at least the second carbon atom removed from the silicon and R N(O)C H groups and (B) a siloxane containing at least one group represented by the formula:

%IIb R N(O) C sHhSiO wherein R is a member selected from the group consist- .45' atom and Z is a member selected from the group consisting of the alkoxy, aryloxy, monovalent hydrocarbon ing of the aryl groups and the alkyl groups, a has a value of at least two, the R N(O) group is attached to at least the second carbon atom removed from the silicon atom and Z is a member selected from the group 0011- sisting of the alkoxy, aryloxy, monovalent hydrocarbon and R N(O)C H groups.

3. A silane represented by the formula:

wherein the -C,, I-I group is a polymethylene' chain, a has a value from ,3 to 5, and Z' is an alkoxy group.

4. A siloxane containing at least one group represented by the formula:

Z"b R2N(O) C.HhS l0 wherein R is a member selected from the group consisting of the aryl and the alkyl groups, a has a value of at least two, the R N(O) group attached to at least the second carbon atom removed from the silicon atom, Z" is a member selected from the group consistingof the wherein the -C,,,H group is a polymethylene chain,

a has a value from 3 to 5, b has a value from 0 to 1 and Z" is a monovalent hydrocarbon-group.

6. A siloxane containing (1) at least one group repre-:

sented by the formula:

2% RzNtO) o.m.si0

: wherein R is a member selected fromthe group consist-.. ing of the aryl and the alkyl groups, a has a value of at least two, the R N(O) group attached to at least. the second carbon atom removed from the silicon atom,

Z" is a member selected from the group consisting of the hydroxy, alkoxy, aryloxy, monovalent hydrocarbon and R N(O)C,H groups and b has a value from 0 to 2,

and (2) at leastone group represented by the formula:

' R.,SiO

8. A process for producing an amine oxide selected from the group consisting of:

(A) a silane represented by the formula:

wherein R is a member selected from the group consisting of the aryl groups and the alkyl groups, a has a value of at least two, the R N(O)- group is attached to at least the second carbon atom removed from the silicon and R N(O)C H groups and (B) a siloxane containing at least one group represented by the formula:

IIb

R,N(o) oflnsio 2 wherein R is a member selected from the group consisting of the aryl and the alkyl groups, a has a value of at least two, the R N(O)- group attached to at least the second carbon atom removed from the silicon atom,

Z" is a'member selected from the group consisting of the hydroxy, alkoxy, aryloxy, monovalent hydrocarbon and ;R N(O)C,,H groups and b has a value from 0 to 2,

which process comprises forming a mixture of (1) an selected from the group consist- 7 wherein R and a have the above-defined meanings'and Y is amember selected from the group consisting of the allroxy, aryloxy, monovalent hydrocarbon and Z'N a Za (D) a siloxane containing at least one group represented by the formula: v 1 V? Rmemasio a 2 wherein R, :a and b have the above-defined m'eanings and Y" is a member selected from theg'roup consisting of the hydroxyl, alkoxy, aryloxy, monovalent hydrocarbon and-R NCgI-I groups and (2) an oxidizing agent and maintaining the mixture at a temperaturefrorn 10 C. to 40 C. to cause the aminosilicon compound and the oxidizing agent to react to produce the amine oxide.

9. A process for producing an amine oxide represented by the formula:

wherein the C H group is a polymethylene chain, ah'asa value from 3 to 5, and Z is an alkoxy group, said process comprising forming a mixture of an aminosilane represented by the formula:

wherein a has the above-defined meaning and Y is an alkoxy group, an oxidizing agentselectedfr'om the group consisting of perbenzoic acid and peracetic acid and an anhydrous solvent in which the aminosilane and the oxidizing agent are soluble and maintaining the mixture at a temperature from 10 C. to 40 C. to cause the aminosila'ne and the oxidizing agent to react to produce the amine oxide.

10. A process for producing an amine oxide free of olefinic unsaturation and containing at least one group represented by the formula:

Memo cuEntsio wherein the -C,,H group is a polymethylene chain,

whats a value from 3 to 5, b has a value from to I v and Z is a monovalent hydrocarbon group, said process comprising forming a mixtureof asiloxane free of olefinic unsaturation and containing at least one group represented by the formula:

lm, MetNmHhs'iQ V 2 wherein the a and b have the above defined meanings and Y"? is a monovalent hydrocarbon group, hydrogen peroxide and water and maintaining the mixture at a temperature from C. to 40 C. to cause the lattermentioned siloxane and the peroxide to react to produce the amine oxides. 7

11. A process for producing an amine oxide represented by the formula:

sisting of the alkoxy, aryloxy, mo'n'ovalent hydrocarbon and C H groups and a has a value of at least two and (B) a 'siloxane containing at least one group represented by the formula:

wherein a has a value of at least two, b has a value from 0 to 2 and Z""' is a member selected from the group consisting of the alkoxy, aryloxy, monovalent hydrocarbon, hydroxy and C H groups, which process comprises heating an amine oxide selected from the group consisting of:

(C) a sil-ane represented by the formula:

z wi aHas 't wherein R is a member selected from thegroup consisting of the aryl groups and the alkyl groups, a has a value of at least two, the R N(O) group is attached to at,

least the second carbon atom removed from the silicon atom and Z is a member selected from the group con-' sisting of the alkoxy, aryloxyl, monovalent hydrocarbon and R N(O)C,,H groups and (D) a siloxane containing at least one group represented by the formula:

V [lb aN( C,H2aSiO' wherein R is a member selected from the group consisting of the aryl and the alkyl groups, a has a value of at least two, the R N(O) group attached to at least the second carbon atom removed from the silicon atom Z" is a member selected from the group consisting of the hydroxy, alkoxyl, aryloxy, monovalent hydrocarbon and R N(O)C I-I groups and b has a value from 0 to 2, to a temperature sulficiently elevated to produce the alkenylsilicon compound.

13. A process for producing an alkenylsilane represented by the formula:

' wherein Z"" is a member selected from the group consi'sting of the alkoxy, aryloxy, monovalent hydrocarbon and C H groups and a has a value of at least two,

said process comprising heating an aminos'ilaile repre' sented by the formula:

R N O C H SiZ' wherein R is a monovalent hydrocarbon group, a has a value of at least two, the R N(O) group is attached to at least the second carbon atom removed from silicon and Z is a member selected from the group-consisting of the alkoxy, aryloxy, monovalent hydrocarbon and R N(O),C,;H groups to a temperature from C. to- 200" C. a

14. A process for producing a 'siloxane containing at least one group represented by the formula:'

c.m. isio wherein a has a value of at least tw0,"b has a value from 0 to 2 and Z""' isa member selected from the group consisting of the alkoxy, aryloxy,"mono'va1ent hydrocarbon, hydroxy and C I-I groups, said'proces's'comprising heating a siloxane containing at least one group represented by theformula:

wherein R is a monovalent hydrocarbon group, a has a value of at least two, the R N(O) group is attached to at least the second carbon atom removed from silicon, b has a value from O to 2 and Z is a member selected from the group consisting of the alkoxy, aryloxy, hydroxy, monovalent hydrocarbon and R N(O)C H groups to a temperature from 75 C. to 200 C.

15. A process for producing allyltrimethylsilane which comprises heating a silane represented by the formula: Me N(O) (CH SiMe to -a temperature from 90 C. to 115 C.

16. A silane represented by the formula:

wherein R is a member selected from the group consisting of the aryl groups and the alkyl groups, a has a value of at least three, the R N(O)-- group is attached to at least the third carbon atom removed from the silicon atom and Z is a member selected from the group consisting of the alkoxy, aryloxy, monovalent hydrocarbon and R N(O)C,,H groups.

17. A siloxane containing at least one group represented by the formula:

l Elmo CaHhSi03 b wherein R is a member selected from the group consisting of the aryl and the alkyl groups, a has a value of at least three, the R N(O) group attached to at least the third carbon atom removed from the silicon atom, Z is a member selected from the group consisting of the hydroxy, alkoxy, aryloxy, monovalent hydrocarbon and 10 R N(O)CgH groups and b has a value from 0 to 2, and (2) at least one group represented by the formula: R' SiO wherein R' is a monovalent hydrocarbon group and c has a value from 0 to 3.

19. A process for producing an alkenylsilane represented by the formula:

wherein Z"" is a member selected from the group consisting of the alkoxy, aryloxy, monovalent hydrocarbon and C H groups and a has a value of at least three, said process comprising heating an aminosilane represented by the formula:

wherein R is a monovalent hydrocarbon group, a has a value of at least three, the R N(O) group is attached to at least the third carbon atom removed from silicon and Z is a member selected from the group consisting of the alkoxy, aryloxy, monovalent hydrocarbon and R N(O)C,,H groups to a temperature from C. to 200 C.

20. A process for producing a siloxane containing at least one group represented by the formula:

wherein a has a value of at least three, b has a value from 0 to 2, Z" is a member selected from the group consisting of the alkoxy, aryloxy, monovalent hydrocarbon, hydroxy and C H groups, said process comprising heating a siloxane containing at least one group represented by the formula:

zllb R|N(O)C.H:-S'iO wherein R is a monovalent hydrocarbon group, a has a value of at least three, the R N(O) group is attached to at least the third carbon atom removed from silicon, b has a value from 0 to 2, and Z" is a member selected from the group consisting of the alkoxy, aryloxy, hydroxy, monovalent hydrocarbon and R N(O)C,,H groups to a temperature from 75 C. to 200 C.

No references cited.

UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent N0 2,955, 127 October 4, 1960 Roscoe A. Pike It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 61, after the arrow, the right-hand portion of the formula should appear as shown below instead of as in the patent:

R N(O)C H Si column 3, line 75, after "-alkenylsilicon" insert compounds column 5, line 58, column 6, lines 10, 32, and 65, column 8, line 34, and column 9, lines 33 and 48, after "group", each occurrence, insert is Eg L) Signed and sealed this 1st day of August 1961. 1 CS! ERNEST W. SWIDER DAVID L. LADD Attesting Officer Commissioner of Patents 

1. AN AMINE OXIDE SELECTED FROM THE GROUP CONSISTING OF: (A) A SILANE REPRESENTED BY THE FORMULA:
 12. A PROCESS FOR PRODUCING AN ALKENYLSILICON COMPOUND SELECTED FROM THE GROUP CONSISTING OF: (A) AN ALKENYLSILANE REPRESENTED BY THE FORMULA: 